Method and means for shaping felts of frangible fibers



May 10, 1938. E. R. POWELL METHOD AND MEANS FOR SHAPING FELTS OF FRANGIBLE FIBERS Filed April 7, 1934 2 Sheets-Sheet 1 IN VENT OR. Edward R. Powell; BY 79. Z. 64 17 ATTORNEY May l0, 1938.

METHOD AND MEANS FOR srmrme FELTS 0F FRANGIBLE FIBERS Filed April 7, 1934 2 Sheets-Sheet 2 INVENTOR' Edward A TTORNE Y E. R. POWELL ,116,663.

Patented May 10, 1938- PATENT OFFICE METHOD MEANS FOR SHAPING FELTS OF FRANGIBLE FIBERS Edward B. Powell, Alexandria, Ind., assignor to Johns-Manville-Corporation, New York, N. Y a corporation of New York Application April 7, 1934, Serial No. 719,478

a Claims.

This invention relates to a method and means for shaping felts of frangible fibers of I the type of mineral wool and is a continuation, in part, of my U. S. Patent 1,864,317. I a

In forming a felt of mineral wool, it is customary to melt a suitable slag, rock, or other selected material, allow the molten material to fall in a small stream into a blast of steam, introduce the thus formed suspension of fibers in the gaseous mixture of steam and air into a settling chamber, and permit settling of the fibers therein, to form a felt upon the bottom of the chamber. There has been described also the use, as the bottom member of the settling chamber, of a conveyor of gauze or the like upon which the felt forms; such a conveyor discharges the felt continuously from the chamber. Likewise, there has been known the use of various binder materials, to coat the suspended fibers of mineral wool and to settle therewith as an ingredient of the felt.

In preparing aeriformed felts of frangible fibers of the type of mineral wool, there has been difficulty heretofore in truing (shaping) and maintaining the established shape of the side edge portions of the felt. Since these fibers are fragile as compared to animal fibers and since the felt, as formed, contacts at its edges with members which limit the width of the felt, say, with the sides of removal of the felt from this settling chamber, as

by conveying the felt through the chamber, has been found to result in tearing and injury to the edges of the felt.

vide means and a method of forming a felt, of this type, in a settling chamber and removing it therefrom, without tearing or distortion of the edges of the felt by friction against the sides of the equipment in which the felt is formed. A further object is to form a felt comprising frangible fibers and a selected proportion of binder, deposited thereover, adapted to be yieldable when warm and relatively stiif when cold, shape the edge portions of felt while the binder therein is in yieldable condition, remove the felt with shaped edges from the settling chamber, and allow the felt to cool, whereby the binder is 50 stiffened and the established shape of the edge portion made substantially permanent. Another object of the invention is to' provide a settling chamber having walls adapted to facilitate proper distribution of the fibers over the selected area the bottom portion of the settling chamber, the

It is an object of the present invention to pro 3 of the bottom member of the settling chamber,

with minimized falling of the fibers from the walls in the form of large clusters.

Other objects and advantages will appear from the detailed description that follows.

I An embodiment of the invention that is preferred at this time is illustrated in the drawings, in which Fig. 1 is a side elevational view, partly diagrammatic, of an apparatus suitable for use in accordance with the present invention;

Fig. 2 is a cross sectional view on the broken line 22 of Fig. 1;

Fig.2a is a cross sectional view on line 2a---2a of Fig. 1;

Fig. 3 is a sectional plan view. on line 33 of Fig. 1; I

Fig. 4 is a similar sectional plan view of a modification of the invention;

Fig. 5 is a view, similar to that'of Fig. 1, of a modification of the invention; and

Fig. 6 is a cross sectional view on line 6-6 of Fig. 5.

In the various figures, like reference characters denote like parts. I

There are shown a furnace Ill for melting argillaceous limestone or other suitable material for forming mineral wool fibers, the discharge of the molten material, as a small stream II, and the blast l2 which shreds the stream of molten material into fibers and carries it, as the aeri form suspension l3, into the settling chamber H.

The blast l2 suitably includes a mixture of steam, supplied by the pipe 36, and a binder of the type of a solution of rosin or a hard asphalt, in

heat or solvent softened condition, supplied through the inlet pipe 15, to the steam line 36.

As the fibers settle from the aeriform suspension, they strike the bottom or bottom closing 'member {6 of the settling chamber which, advantageously, is in the form of a conveyor that is gas-permeable. For this conveyor, I have used to advantage 'an endless belt, consisting of a gauze of metal, driven over the pulleys I I and I 8, by driving means indicated generally by IS.

The material settling upon the conveyor I6 isconfined between upstanding edge-shaping members 20 and 2| contacting, respectively, with the two side edges of the felt, positioning the fibers therein, as the felt forms, and limiting the width of the felt. These side elements 20 and 2 I may be endless belt conveyors moving over the end rollers 3|, 3!, and 29,.30 respectively. In the portion in contact with the felt, these edge conveyors move in the same direction as the upper part of the bottom conveyor l6, that is, in the direction of discharge of the felt from the settling chamber. I have used to advantage a combination in which these three endless belts move at approximately the same speed, the driving means i9 moving all the elements I6, 20, and 2i.

The settling chamber has side walls 22 and 23 that are sloped and that direct fibers settling thereupon to the conveyor it. It has been found that, for best operating results, the lower portions of these side walls of the settling chamber should be inclined from the horizontal at an angle greater than suitably of the order of to 72. With such an inclination, there is eliminated the tendency of the fibers to hang upon the side walls or to fall therefrom in large bunches or clusters, these being difliculties experienced when the side walls are inclined less steeply than at the critical angle stated. At the same time, the felt is caused to be of substan- I .edges of the felt are disposed well inside the edge of the conveyor it, that is, at some position between the edge and the central portion of the conveyor, and fibers falling from the walls do not accumulate at the extreme edge portions of the conveyor.

The side walls of the settling chamber may define between them an irregular sinuous channel, say, a zigzag path extending over the conveyor belt, from side to side, and, in general, in the direction of travel of the conveyor, as described in my said patent.

- In forming a felt of satisfactory nature, with the equipment described, there may be utilized also the joint effect of the exhauster 25, say, a suction blower, which removes gases from the bottom of the settling chamber, at a position adjacent to the end-thereof into which the suspension of the fibers in the gas mixture is first blown, and through'the gas-permeable member I 6. With such a position of'the exhauster, there is a tendency, it is believed, for the gases entering the chamber to be deflected downward in the first part of the chamber, thus causing partial separation, at the inlet portion of the chamber, of gas which, otherwise, might cause increased turbulence in other parts of the chamber, with disturbing effect upon the uniformity of settling of fibers therein.

It will be understood that gases may also escape from the chamber through the vent or ventilator 26 located at the top of the chamber.

The idler roller .28 serves to slightly compress the felt 35.

In the modification shown in Fig. 4, the side conveyors or edge-shaping members, contacting with the edges of the felt, converge in the direction of movement of the conveyor iii.

In the modification shown in Figs. 5 and 6, the

edge-shaping members move with respect to the side walls of the settling chamber, as is the case with the embodiment previously described, but, in the present modification, move in opposite directions, in reciprocating manner, to give a smoothing effect to the edges of the felt, as the felt is being formed. These edge-shaping members 33 and 34 are suitably metal plates which are sufllciently stiff to retain their preestablished alignment and are moved relatively rapidly, to and fro, by an eccentrically mounted driving rod 31 or by other suitable means. The idler roll and driving means for the conveyor l6 may be constituted as illustrated in Fig. 1.

The operation of the apparatus will be described, first, in connection with the embodiments illustrated in Figs. 1-4.

As the fibers settle from the aeriform suspension I3, they fall, in part, directly upon the bottom member l6 and partly upon the side walls 22 and 23 of the settling chamber, from which walls the fibers are directed to the conveyor i6. Because of the overhang of the lower edges of the said walls, inside the edges of the conveyor it, the fibers falling upon the said conveyor are confined between the side conveyors 20 and 2|. The side conveyors not only establish the width of the felt, but also shape the edges of the felt; a fiber that, as it falls, might otherwise extend outwardly, beyond the desired edge, is turned backwardly or oriented by the element 20 or 2! and is quickly interlocked in its thus established position by other fibers deposited subsequently thereupon. These said other fibers, also, are likewise oriented or placed so that the edge of the felt is shaped continuously and the fibers therein interlocked with each other, as the felt is being built up.

At the same time, the conveyor l6 and the elements 20 and 2 I, in the portions in contact with the felt, move, at the same speed, for example, towards the position of discharge of the felt from the settling chamber, whereby the felt is delivered from the chamber without substantial friction or tearing of the edge. portions of the felt. This result is to be distinguished clearly from felts made in the conventional way in which the edge of the felt, as it is moved through the felting chamber, are dragged against the stationary sides of the heretofore known type of settling chamber.

In the modification shown in Fig. 4, the conveyor l6 transports the felt between the edgeshaping members 20 and 2! which, in this instance, being convergent in the direction of movement of the conveyor it, give to the felt'a moderate compression in an edgewise manner. This serves to further interlock the fibers and strengthen the edge portions of the felt.

If the form of the apparatusshown in Figs. 5 and 6 is used, the operation is the same, the reciprocating plates 33 and 34 replacing the side or edge-shaping belts 20 and 2|.

Finally, the felt is moderately compressed by the idler roller 28 which rides upon the felt at It will be understood, also, that the details given are for the purpose of illustration, not restriction, and that variations may be made therefrom within the scope of the appended claims.

What I claim is: i

1. In forming a felt of frangible fibers of the type of mineral wool, the method which comprises forming an aeriform suspension of the fibers, settling the fibers therefrom into a felt upon a bottom element and between edge-shaping members, moving the said members, in reciprocating manner, as the felt is being formed, thereby shaping the edge portions of the felt, depositing additional fibers upon the thus shaped edge portions, to interlock the fibers therein in previously established position, and removing the resulting felt from said element, with preservation of the shaped edge portions of the felt,

2. Apparatus for forming a felt of frangible fibers of the type of mineral wool comprising means for forming an aeriform suspension of the fibers, means for introducing the suspension into a settling chamber,'conveyor means constituting the bottom member of the settling chambenand adapted to receive fibers settled as afelt thereon and to transport the felt through and finally out of the chamber, means includingiupstanding elements moving in reciprocating manner with respect to the conveyor means for shaping the edges of the felt continuously as the felt.

is formed. and for minimizing tearing of the side edges of the felt, as the felt is conveyed through the chamber. I a

3. An apparatus for forming a felt of frangible fibers of the type of mineral wool comprising, in combination, means for forming an aeriform suspension of the fibers to be settled, means for introducing the suspension into a settling chamber, a bottom member of the settling chamber adapted to receive the settled fibers and to convey them therefrom, and shaping members adapted to shapethe two edges of the felt, the said shaping members including each an upstanding reciprocating element providing a smoothing action upon the edges of the felt.

4. In forming a felt of frangible fibers of the type of mineral wool, the ,method which com- .a felted body upon a conveyer and continuously advancing said conveyer and deposited body of fibers, contacting theside edges of the felted body with moving surfaces during advance of the body to confine the side edges and thereby shape the body while the fibers are substantially above felted fibers before they reach normal temper-- ature for-compressing them into a finished felted body.

6. The method of forming a felted body of fibers comprising forming a mass of fibers from heat liquifled material, depositingsaid fibers in a felted body upon a conveyor and continuously advancing said conveyor and deposited body of fibers, contacting the side edges of the felted body with moving, converging surfaces during advance of the body to confine and compress the side edges and thereby shape the body while the fibers are substantially above normal temperature but without tearing of the body, and applying pressure to a face of said felted fibers before they reach normal temperature for compressing them into a finished felted body.

"I. An apparatus for forming felted fibrous bodies comprising a device for forming discrete fibers from heat liquified mineral matter, a travelling conveyor for receiving and advancing said fibers,.means movable substantially longitudinally of the conveyer for compressing and confining a side edge of the body of fibers on said conveyor without tearing said body, and means permeable memberforming the bottom of thesaid chamber predominantly at a position remote from the part of the chamber into which the said suspension is first introduced, and withdrawing a large proportion of the said gas from the chamber through the said member at a position adjacent to the said part of the chamber, thereby-causing said large proportion of the gas to. take a path through the chamber which turns more sharply than the path of the fibers so as to separate the gas from the fibers. 

